Harris SS – The associations reported from the observational studies show that vitamin D supplementation could potentially have a strong preventive effect on some of the conditions such as type 2 diabetes (T2D) and some forms of cardiovascular disease (CVD) and hypertension and could reduce race–related disparities in their prevalence.

African Americans have higher rates of type 2 diabetes (T2D) and some forms of cardiovascular disease (CVD) than do European Americans.

African Americans also have much higher rates of vitamin D deficiency.

There is emerging evidence that vitamin D deficiency may be a risk factor for hypertension, T2D, and CVD, but the extent to which racial disparities in disease rates are explained by racial differences in vitamin D status is uncertain.

Despite a large number of observational studies and a limited number of clinical trials that examined 25–hydroxyvitamin D [25(OH)D] concentrations as a potential determinant of CVD and T2D or its precursors, it remains uncertain whether improving vitamin D status would reduce risk of these conditions in the general US population or in African Americans specifically.